Jessica Alba 'didn't believe' "Sin City 2" would happen

The 31-year-old actress is set to reprise her role as Nancy in Robert Rodriguez's and Frank Miller's follow-up to the 2005 neo-noir thriller, and while she describes being back on set again as ''a dream'', Jessica admits the delay made her doubt whether it would happen or not.

In an interview with Collider.com, she explained: ''Every six months to a year it was like, 'We're going to do it, when's the next one coming? Oh yeah, we're going to do it. We're going to do it. We're going to do it.' And then at a certain point it was just like OK. I just didn't believe it.

''It was like, 'We're going to start in the summer, we're going to start in the fall,' but then when we actually got the start date and I was there on the set it was like a dream. I was like, 'Am I really here? Are we really here? OK, just making sure.' So yeah, it was surreal and for all of us it's really cool.''

Jessica enjoyed watching directors Robert and Frank ''inspire'' one another when creating the film and thinks the end result will be even better than the original.

She continued: ''Mine is an original story so there wasn't a lot to base it off of, but Frank has been drawing. So it's just crazy.

''It was neat to see their process, Robert and Frank's, and their collaboration and what they inspire from each other and get out of each other and what they're creating. It's really like the 2.0 version of 'Sin City' and it's pretty amazing.''

'Sin City: A Dame to Kill For' is tentatively due for release in October.